diff options
Diffstat (limited to 'tcl8.6/compat/waitpid.c')
| -rw-r--r-- | tcl8.6/compat/waitpid.c | 168 |
1 files changed, 0 insertions, 168 deletions
diff --git a/tcl8.6/compat/waitpid.c b/tcl8.6/compat/waitpid.c deleted file mode 100644 index e03275a..0000000 --- a/tcl8.6/compat/waitpid.c +++ /dev/null @@ -1,168 +0,0 @@ -/* - * waitpid.c -- - * - * This procedure emulates the POSIX waitpid kernel call on BSD systems - * that don't have waitpid but do have wait3. This code is based on a - * prototype version written by Mark Diekhans and Karl Lehenbauer. - * - * Copyright (c) 1993 The Regents of the University of California. - * Copyright (c) 1994 Sun Microsystems, Inc. - * - * See the file "license.terms" for information on usage and redistribution of - * this file, and for a DISCLAIMER OF ALL WARRANTIES. - */ - -#include "tclPort.h" - -#ifndef pid_t -#define pid_t int -#endif - -/* - * A linked list of the following structures is used to keep track of - * processes for which we received notification from the kernel, but the - * application hasn't waited for them yet (this can happen because wait may - * not return the process we really want). We save the information here until - * the application finally does wait for the process. - */ - -typedef struct WaitInfo { - pid_t pid; /* Pid of process that exited. */ - WAIT_STATUS_TYPE status; /* Status returned when child exited or - * suspended. */ - struct WaitInfo *nextPtr; /* Next in list of exited processes. */ -} WaitInfo; - -static WaitInfo *deadList = NULL; - /* First in list of all dead processes. */ - -/* - *---------------------------------------------------------------------- - * - * waitpid -- - * - * This procedure emulates the functionality of the POSIX waitpid kernel - * call, using the BSD wait3 kernel call. Note: it doesn't emulate - * absolutely all of the waitpid functionality, in that it doesn't - * support pid's of 0 or < -1. - * - * Results: - * -1 is returned if there is an error in the wait kernel call. Otherwise - * the pid of an exited or suspended process is returned and *statusPtr - * is set to the status value of the process. - * - * Side effects: - * None. - * - *---------------------------------------------------------------------- - */ - -#ifdef waitpid -# undef waitpid -#endif - -pid_t -waitpid( - pid_t pid, /* The pid to wait on. Must be -1 or greater - * than zero. */ - int *statusPtr, /* Where to store wait status for the - * process. */ - int options) /* OR'ed combination of WNOHANG and - * WUNTRACED. */ -{ - register WaitInfo *waitPtr, *prevPtr; - pid_t result; - WAIT_STATUS_TYPE status; - - if ((pid < -1) || (pid == 0)) { - errno = EINVAL; - return -1; - } - - /* - * See if there's a suitable process that has already stopped or exited. - * If so, remove it from the list of exited processes and return its - * information. - */ - - for (waitPtr = deadList, prevPtr = NULL; waitPtr != NULL; - prevPtr = waitPtr, waitPtr = waitPtr->nextPtr) { - if ((pid != waitPtr->pid) && (pid != -1)) { - continue; - } - if (!(options & WUNTRACED) && (WIFSTOPPED(waitPtr->status))) { - continue; - } - result = waitPtr->pid; - *statusPtr = *((int *) &waitPtr->status); - if (prevPtr == NULL) { - deadList = waitPtr->nextPtr; - } else { - prevPtr->nextPtr = waitPtr->nextPtr; - } - ckfree((char *) waitPtr); - return result; - } - - /* - * Wait for any process to stop or exit. If it's an acceptable one then - * return it to the caller; otherwise store information about it in the - * list of exited processes and try again. On systems that have only wait - * but not wait3, there are several situations we can't handle, but we do - * the best we can (e.g. can still handle some combinations of options by - * invoking wait instead of wait3). - */ - - while (1) { -#if NO_WAIT3 - if (options & WNOHANG) { - return 0; - } - if (options != 0) { - errno = EINVAL; - return -1; - } - result = wait(&status); -#else - result = wait3(&status, options, 0); -#endif - if ((result == -1) && (errno == EINTR)) { - continue; - } - if (result <= 0) { - return result; - } - - if ((pid != result) && (pid != -1)) { - goto saveInfo; - } - if (!(options & WUNTRACED) && (WIFSTOPPED(status))) { - goto saveInfo; - } - *statusPtr = *((int *) &status); - return result; - - /* - * Can't return this info to caller. Save it in the list of stopped or - * exited processes. Tricky point: first check for an existing entry - * for the process and overwrite it if it exists (e.g. a previously - * stopped process might now be dead). - */ - - saveInfo: - for (waitPtr = deadList; waitPtr != NULL; waitPtr = waitPtr->nextPtr) { - if (waitPtr->pid == result) { - waitPtr->status = status; - goto waitAgain; - } - } - waitPtr = (WaitInfo *) ckalloc(sizeof(WaitInfo)); - waitPtr->pid = result; - waitPtr->status = status; - waitPtr->nextPtr = deadList; - deadList = waitPtr; - - waitAgain: - continue; - } -} |